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What is meant by the contour “interval” on a topographic map?

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1. In cartography, a contour interval is any space between vertical lines on a topographic map or globe, representing a difference in elevation between the lines. Close contour lines indicate a steep slope; more wide-apart contour lines indicate a shallow slope. Two or more contour lines merging indicates a cliff. So the wider the 'interval' the more level or flat the terrain.
2. i think it every 5 lines is darkend or something u in 8th grade or something lol
3. The "interval" means the difference in height between each line.
4. Contour lines on a topographic map join points of equal elevation. Therefore a contour line is always the same distance above sea level. The contour interval is the vertical distance between two adjoining contour lines. For example, if the contour interval on a map was 50 meters, then the lines would be 50 meters apart measured vertically. The steeper the terrain, the closer the contour lines will be.
5. The contour interval is the difference in elevation between adjacent contour lines. On USGS maps, this is very often 2 feet. The contour lines for multiples of 10 feet in elevation will be heavier, and between the heavier lines, like say for elevations 420 and 430, you will have four lighter lines which represent the elevations 422, 424, 426 and 428 feet.